An elevation of privilege vulnerability exists in Dynamics On-Premise v9, aka 'Dynamics On-Premise Elevation of Privilege Vulnerability'.

An elevation of privilege vulnerability exists in Dynamics On-Premise v9. An attacker who successfully exploited the vulnerability could leverage a customizer privilege within Dynamics to gain control of the Web Role hosting the Dynamics installation.
To exploit this vulnerability, an attacker needs to have credentials for a user that has permission to author customized business rules in Dynamics, and persist XAML script in a way that causes it to be interpreted as code.
The update addresses the vulnerability by restricting XAML activities to a whitelisted set.